Previously, many retail operations have utilized a plurality of point of sale registers, each coupled to a central computer. Each of the registers contain a processor and are coupled to one of a plurality of optical character readers, or OCR's. Each of the OCR's scan alphanumeric product identification information from products to be purchased and transfer this scanned information to its respective register.
The central computer stores information correlating the product identification information for each of the products to the product's specific sales price. The register communicates with the central computer to obtain the specific price of each item scanned. This eliminates a requirement to individually key into the register the price of each item purchased. However, while most products include a standard bar code encoded product identifier placed on the product by the manufacturer, alphanumeric product information must be added for each specific item by the particular retail operation.
Often the purchases are charged on a credit card. The central computer further contains information regarding an account status of each outstanding credit card account. If the credit card is so equipped, the OCR scans an alphanumeric account number representation from the credit card. In this manner, the information can be transferred to the central computer to determine the account status of that particular credit account.
If the central computer determines that no additional credit is to be allowed, and the purchaser still desires to make the purchase by credit card, a phone call is manually initiated to a human operator who has authority to override the central computer. The store clerk must first inform the operator of the particular credit account number and the amount of additional credit desired, as by utilizing the touch-tone pad of the telephone. However, it is generally recognized by those skilled in the art as an inherent problem that this form of data entry often results in errors, requiring time consuming reentry of the information by the store clerk.
Many credit cards are provided with a magnetic stripe onto which data such as its respective credit account number and expiration date, is stored. The data stored on the magnetic stripe of such credit cards is scanned by moving the magnetic stripe past a magnetic head of a magnetic stripe reader which reads the data. However, registers have been incapable of receiving and utilizing this data. Further, the card has been capable of being passed by the magnetic head in only one, predetermined direction, referred to as a forward scan, but such "unidirectional scanning" often makes it physically awkward to scan the credit card.
Another limiting feature of point of sale register systems is that standard microprocessors typically have a single input/output (or I/O) port. Thus, when it has been desirable for the microprocessor to communicate with a plurality of peripheral devices, complex circuitry has been required.
The invention disclosed herein is provided to overcome some or all of the above problems.